Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Feedback Carburetor System: Description
The feedback carburetor system maintains the proper air/fuel ratio during engine operation. Air control valves are used to by-pass additional air into the intake manifold to adjust a temporarily rich mixture condition. The system consists of 2 feedback systems, the "X" and "M" systems.
The "X" system consists of an feedback control solenoid valve (Prelude), frequency solenoid B, constant vacuum valve (Prelude), check valves A, B, C and E, surge tanks A and B, and the control unit. Surge tank A is used as a reservoir. Surge tank B is used to dampen vacuum pulses to the air control valve B.
The "M" system consists of a check valve A (Prelude), air control valve A, frequency solenoid valve A and the control unit.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.